Francesco Puleo

Gut failure in the ICU.

The role of dysfunction of the gastrointestinal tract in the pathogenesis of multiple organ failure (MOF) complicating the course of critically ill patients has been suspected for more than 40 years. However, several hypotheses have been proposed and sometimes refuted to establish a link. This review summarizes the current knowledge on gastrointestinal physiology and recapitulates existing evidence on the link between gastrointestinal dysfunction and MOF. The gastrointestinal tract has various functions apart from digestion. It produces hormones with local and systemic effects, plays a major role in immunological function, and serves as a barrier against antigens within its lumen. Gastrointestinal dysfunction or gut failure is frequently encountered in critical care patients and is associated with bacterial translocation, which can lead to the development of sepsis, initiation of a cytokine-mediated systemic inflammatory response syndrome (SIRS), multiple organ dysfunction syndrome (MODS), and death. The aim of this manuscript is to define gut failure, to review physiopathological mechanisms and clinical implications, and, finally, to suggest preventive measures.

Sonic Hedgehog and Gli1 Expression Predict Outcome in Resected Pancreatic Adenocarcinoma

Purpose: Aberrant activation of the hedgehog (Hh) pathway is implicated in pancreatic ductal adenocarcinoma (PDAC) tumorigenesis. We investigated the prognostic and predictive value of four Hh signaling proteins and of the tumor stromal density. Experimental Design: Using tissue microarray and immunohistochemistry, the expression of Shh, Gli1, SMO, and PTCH1 was assessed in 567 patients from three independent cohorts who underwent surgical resection for PDAC. In 82 patients, the tumor stromal index (SI) was calculated, and its association with overall survival (OS) and disease-free survival (DFS) was investigated. Results: Shh and Gli1 protein abundance were independent prognostic factors in resected PDACs; low expressors for those proteins experiencing a better OS and DFS. The combination of Shh and Gli1 levels was the most significant predictor for OS and defined 3 clinically relevant subgroups of patients with different prognosis (Gli1 and Shh low; HR set at 1 vs. 3.08 for Shh or Gli1 high vs. 5.69 for Shh and Gli1 high; P < 0.001). The two validating cohorts recapitulated the findings of the training cohort. After further stratification by lymph node status, the prognostic significance of combined Shh and Gli1 was maintained. The tumor SI was correlated with Shh levels and was significantly associated with OS (P = 0.023). Conclusions: Shh and Gli1 are prognostic biomarkers for patients with resected PDAC. Clin Cancer Res; 21(5); 1215–24. ©2014 AACR.

New challenges in perioperative management of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related death in the industrialized world. Despite progress in the understanding of the molecular and genetic basis of this disease, the 5-year survival rate has remained low and usually does not exceed 5%. Only 20%-25% of patients present with potentially resectable disease and surgery represents the only chance for a cure. After decades of gemcitabine hegemony and limited therapeutic options, more active chemotherapies are emerging in advanced PDAC, like 5-Fluorouracil, folinic acid, irinotecan and oxaliplatin and nab-paclitaxel plus gemcitabine, that have profoundly impacted therapeutic possibilities. PDAC is considered a systemic disease because of the high rate of relapse after curative surgery in patients with resectable disease at diagnosis. Neoadjuvant strategies in resectable, borderline resectable, or locally advanced pancreatic cancer may improve outcomes. Incorporation of tissue biomarker testing and imaging techniques into preoperative strategies should allow clinicians to identify patients who may ultimately achieve curative benefit from surgery. This review summarizes current knowledge of adjuvant and neoadjuvant treatment for PDAC and discusses the rationale for moving from adjuvant to preoperative and perioperative therapeutic strategies in the current era of more active chemotherapies and personalized medicine. We also discuss the integration of good specimen collection, tissue biomarkers, and imaging tools into newly designed preoperative and perioperative strategies.

Assessing the learning curve for totally laparoscopic major-complex liver resections: a single hepatobiliary surgeon experience.

Background: Encouraging results have been reported in terms of feasibility, safety, and oncologic, outcomes even for major (≥3 segments) or complex for location-specific (right posterior segments) laparoscopic liver resections. Despite this, technically challenging issues and advanced laparoscopic skills required to perform it have limited its use in few highly specialized centers. The aim of this study was to assess the learning curve for major-complex totally laparoscopic liver resections (TLLR) performed by a single HPB surgeon. Materials and Methods: From October 2008 to February 2012, a total of 70 TLLR were performed; 24 (33.3%) were major-complex resections. This series was divided in 2 groups according to time of operation: group A (12 cases early series) and group B (12 cases late series); perioperative outcomes were retrospectively analyzed and compared. Results: Comparing the 2 groups, a statistically significant improvement was found in terms of operative time (P=0.017), blood loss (P=0.004), number of cases requiring a Pringle maneuver (P=0.006), and blood transfusion (P=0.001) from case number ten onward. Conclusions: This study shows that a minimum of 10 cases are required to obtain a significant improvement in perioperative outcome for surgeons with specific training on hepatobiliary surgery and advanced laparoscopic surgical procedures. More studies are required to clarify the minimum standard of training to perform safely this kind of advanced laparoscopic liver surgery on a large scale.

DLL4 expression is a prognostic marker and may predict gemcitabine benefit in resected pancreatic cancer

Background:There is an increasing interest for Notch signalling pathway and particularly Delta-like ligand 4 (DLL4) as potential therapeutic target to improve outcome for patients with pancreatic ductal adenocarcinoma (PDAC).Methods:Using immunohistochemistry (IHC) and tissue microarray (TMA), we assessed the expression patterns of DLL4, Notch1 and Notch3 in 151 patients from two independent cohorts of resected PDAC. We investigated the prognostic and the predictive significance of these proteins.Results:High IHC DLL4 expression in cancer cells was associated with worse overall survival (OS) and disease-free survival (DFS) than low DLL4 expression (median OS: 12.9 vs 30.4 months, P=0.004 and median DFS: 8.8 vs 17.4 months, P=0.02). High DLL4 expression remained a significant negative prognostic factor in multivariate analysis (HR for OS: 2.1, P=0.02 and HR for DFS: 2.0, P=0.02). Low DLL4 abundance was associated with a longer OS–only for patients who received an adjuvant gemcitabine-based chemotherapy (P<0.001) but not for patients who did not receive gemcitabine (P=0.72). Furthermore, the interaction test for adjuvant gemcitabine therapy was statistically significant (P<0.001). The validating cohort recapitulated the findings of the training cohort.Conclusions:Low DLL4 abundance in tumour cells may predict the benefit from adjuvant gemcitabine therapy after PDAC resection.

Feasibility of Immunohistochemistry on Endoscopic Ultrasound Fine-Needle Aspiration Samples for Evaluating Predictive Biomarkers in Pancreatic Cancer Management.

either wedged into an intercalated duct cell line or the intercalated duct cell line branching off from that intercalated duct, and there was scant intercellular space without a PAM-stained membrane in portions between endocrine cells and adjacent acinar cells, as well as those intercalated duct cells. The interface portions with scant intercellular space between peripheral islet cells and adjacent peripheral exocrine glands noted in LM observations were also observed with TEM, which revealed a lack of space and no basement membrane (Figs. 1E–G).

Circulating tumor DNA in early response assessment and monitoring of advanced colorectal cancer treated with a multi-kinase inhibitor

Predictive biomarkers are eagerly awaited in advanced colorectal cancer (aCRC). Targeted sequencing performed on tumor and baseline plasma samples in 20 patients with aCRC treated with regorafenib identified 89 tumor-specific mutations of which ≥50% are also present in baseline plasma. Droplet digital PCR (ddPCR) assays were optimized to monitor circulating tumor DNA (ctDNA) levels in plasmatic samples collected throughout the treatment course and showed the importance of using the absolute value for ctDNA rather than the mutant/wild type ratio in monitoring the therapy outcome. High baseline cell free DNA (cfDNA) levels are associated with shorter overall survival (OS) (HR 7.38, P=0.001). An early increase (D14) in mutated copies/mL is associated with a significantly worse PFS (HR 6.12, P=0.008) and OS (HR 8.02, P=0.004). These data suggest a high prognostic value for early ctDNA level changes and support the use of blood-born genomic markers as a tool for treatment.

Stratification of Pancreatic Ductal Adenocarcinomas Based on Tumor and Microenvironment Features

BACKGROUND & AIMS Genomic studies have revealed subtypes of pancreatic ductal adenocarcinoma (PDA) based on their molecular features, but different studies have reported different classification systems. It is a challenge to obtain high-quality, freshly frozen tissue for clinical analysis and determination of PDA subtypes. We aimed to redefine subtypes of PDA using a large number of formalin-fixed and paraffin-embedded PDA samples, which are more amenable to routine clinical evaluation. METHODS We collected PDA samples from 309 consecutive patients who underwent surgery from September 1996 through December 2010 at 4 academic hospitals in Europe; nontumor tissue samples were not included. Samples were formalin fixed and paraffin embedded. DNA and RNA were isolated; gene expression, targeted DNA sequencing, and immunohistochemical analyses were performed. We used independent component analysis to deconvolute normal, tumor, and microenvironment transcriptome patterns in samples. We devised classification systems from an unsupervised analysis using a consensus clustering approach of our data set after removing normal contamination components. We associated subtypes with overall survival and disease-free survival of patients using Cox proportional hazards regression with estimation of hazard ratios and 95% confidence interval. We used The Cancer Genome Consortium and International Cancer Genome Consortium PDA data sets as validation cohorts. RESULTS We validated the previously reported basal-like and classical tumor-specific subtypes of PDAs. We identified features of the PDA, including microenvironment gene expression patterns, that allowed tumors to be categorized into 5 subtypes, called pure basal like, stroma activated, desmoplastic, pure classical, and immune classical. These PDA subtypes have features of cancer cells and immune cells that could be targeted by pharmacologic agents. Tumor subtypes were associated with patient outcomes, based on analysis of our data set and the International Cancer Genome Consortium and The Cancer Genome Consortium PDA data sets. We also observed an exocrine signal associated with acinar cell contamination (from pancreatic tissue). CONCLUSIONS We identified a classification system based on gene expression analysis of formalin-fixed PDA samples. We identified 5 PDA subtypes, based on features of cancer cells and the tumor microenvironment. This system might be used to select therapies and predict patient outcomes. We found evidence that the previously reported exocrine-like (called ADEX) tumor subtype resulted from contamination with pancreatic acinar cells. ArrayExpress accession number: E-MTAB-6134.

Personalized medicine in pancreatic cancer: The revolution has begun

Pancreatic ductal adenocarcinoma carries a dismal prognosis. Both chemotherapy and targeted therapies have been disappointing when administered to unselected populations. Recently, progress has been made in our understanding of the genomic landscape of this cancer which displays remarkable heterogeneity suggesting a reorientation of management and research strategies based on molecular characterization and adapted personalized therapy. Resectable disease offers new opportunities for translational research through functional imaging response evaluation and tumor tissue acquisition before and after neoadjuvant therapy. There is urgent need for clinical trials based on molecular profiling in pancreatic ductal adenocarcinoma. In this review we discuss opportunities and limitations of these new strategies, underlining the importance of tissue acquisition and integration of molecular biomarkers in future molecularly driven clinical trials.